The funeral of the murdered vice-president of Pakistan’s PTI party, Zahra Shahid Hussain, has been held at a mosque in the country’s capital, Karachi.

Zahra Shahid Hussain was shot dead outside her home in Karachi by gunmen on a motorcycle.

PTI leader Imran Khan has blamed one of his political rivals for the killing.

On his Twitter feed, Imran Khan said he was holding the leader of Karachi’s dominant MQM party, Altaf Hussain, responsible for her death – a claim the MQM has strongly denied.

It came as Karachi voted in a partial re-run of Pakistan’s general election.

Police are investigating whether Zahra Shahid Hussain’s killing was the result of an attempted robbery or a politically motivated murder.

Doctors at Karachi’s Jinnah Hospital havesaid their initial examination showed two bullet marks on her body. A full post-mortem report is expected to be released.

Imran Khan, a former captain of Pakistan’s cricket team, said Altaf Hussain, who is in self-imposed exile in London, had “openly threatened PTI workers and leaders through public broadcasts”.

He said he was also holding the British government responsible, as he said he had warned it about Altaf Hussain.

Imran Khan tweeted his accusations from his hospital bed, where he is recovering from a back injury sustained during a fall at an election rally in Lahore.

Last week, police in London confirmed they were investigating complaints that Altaf Hussain had broken UK laws by issuing threats in a speech he made the day after the vote.

In response to accusations of electoral fraud, he is alleged to have threatened his accusers with violence.

The funeral of the murdered vice-president of Pakistan’s PTI party, Zahra Shahid Hussain, has been held at a mosque in Karachi

Altaf Hussain and his supporters say that his remarks were taken out of context. He has lived in the UK since 1991, saying his life would be at risk if he returned to Pakistan.

MQM spokesman Mohammad Anwar said that Imran Khan’s comments were the “groundless, baseless” accusations of a man who had suffered a bitter, unexpected loss in the election.

He said there was only one reason that Imran Khan could have issued a statement of blame just minutes after the killing: “He is behind the murder. He is the mastermind.”

Last Sunday’s electoral re-run in Karachi was ordered after Imran Khan’s party accused the MQM of widespread vote-rigging and intimidation.

The MQM – which took most of the seats in Karachi – denies any irregularities and is boycotting the vote, which is taking place under tight security.

Voter turn-out appeared slow but steady.

The PTI is hoping to win the vote and make inroads in Pakistan’s commercial capital.

Whatever the outcome of the re-run, it will not overturn the overall result of last week’s vote, in which conservative leader Nawaz Sharif secured an unprecedented third term in power.

The MQM is seen as a perpetrator – as well as a victim – of violence in Karachi.

Since the 1980s, it has won every election it has contested there.

But it also stands widely accused of ruling Karachi by fear and through vote-rigging.

The general election on May 11 marked the first transition of power from one democratically elected government since the creation of the state of Pakistan in 1947.

However, the campaign was marred by violence in which about 150 people were killed across the country.

The MQM (Muttahida Qaumi Movement) is supported mainly by Muslim Urdu-speaking people whose families moved to Sindh province at the time of the partition of India in 1947.

Voting in Karachi on May 11 was disrupted by a bomb attack outside the office of the ANP party, in which 11 people were killed and more than 40 injured.

The bombing happened in the Landhi district of Karachi, where Taliban militants are known to be active.

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